Pursuant to Section 906 of the Sarbanes-Oxley
Act of 2002, 18 U.S.C. Section 1350, the undersigned officer of deltathree, Inc. (the “registrant”) does hereby
certify, to such officer’s knowledge, that:

(1)

(2)

the Quarterly
Report on Form 10-Q for the quarter ended September 30, 2012 (the “Form 10-Q”) of
the registrant fully complies with the requirements of section 13(a) or 15(d) of the Securities Exchange Act of 1934; and

the information contained in the Form 10-Q
fairly presents, in all material respects, the financial condition and results of operations of the registrant.

Date: November 14, 2012

By:

/s/ Effi Baruch

Effi Baruch, Chief Executive Officer, President, Senior Vice

President of Operations and Technology and
Secretary

The foregoing certification will not
be deemed “filed” for purposes of Section 18 of the Exchange Act, or otherwise subject to the liability of that section.
Such certification will not be deemed to be incorporated by reference into any filing under the Securities Act or the Exchange
Act, except to the extent that the registrant specifically incorporates it by reference.